package a10_动态规划;

/**
 * <p>
 * a07_不同路径2复习2
 * </p>
 *
 * @author flyduck
 * @since 2025/2/18
 */
public class a07_不同路径2复习2 {
    //dp[i][j]：从起点到达[i,j]有dp[i][j]种方式
    //dp[i][j] = dp[i-1][j] + dp[i][j-1]
    public int uniquePathsWithObstacles(int[][] obstacleGrid) {
        int m = obstacleGrid.length;
        int n = obstacleGrid[0].length;
        int[][] dp = new int[m][n];

        for (int i = 0; i < m; i++) {
            if(obstacleGrid[i][0] == 1){
                break;
            }
            dp[i][0] = 1;
        }

        for (int j = 0; j < n; j++) {
            if(obstacleGrid[0][j] == 1){
                break;
            }
            dp[0][j] = 1;
        }

        for (int i = 1; i < m; i++) {
            for (int j = 1; j < n; j++) {
                if(obstacleGrid[i][j] == 1){
                    dp[i][j] = 0;
                }else {
                    dp[i][j] = dp[i-1][j] + dp[i][j-1];
                }

            }
        }

        return dp[m-1][n-1];
    }
}
